US Airways B752 near Phoenix on Jan 16th 2014, engine vibrations

A US Airways Boeing 757-200, registration N935UW performing flight US-714 from Phoenix,AZ to Philadelphia,PA (USA), was climbing out of Phoenix when the crew requested to level off at FL210 reporting they had an engine (RB211) problem later adding the left hand engine had been reduced to idle thrust due to vibrations. The aircraft burned off fuel and returned to Phoenix for a safe landing about 80 minutes after departure.

The flight was cancelled, the passengers were rebooked onto other flights.